1. Field of the Invention
The present invention relates to an electric vacuum cleaner that comprises a cleaner body incorporating an intake fan for sucking dust, and is supported in a floating manner on a surface to be cleaned by the function of exhaust air from the intake fan.
2. Description of Related Art
In an electric vacuum cleaner that sucks dust by using negative pressure produced on the suction side of an intake fan and collects the dust in a dust collection chamber provided in a mid part of an intake channel, the intake fan including a drive motor is a heavy load. Therefore, in general, the cleaner body incorporating the intake fan is supported by carrier wheels, a dust suction nozzle is connected to the clearer body and attached to an end of an extension hose connected to the suction side of the intake fan, the dust suction nozzle is operated by holding a grip provided in a mid part of the extension hose, and a dust suction port formed in the dust suction nozzle is pressed against a surface to be cleaned and slipped so as to suck dust on the surface to be cleaned.
Such an electric vacuum cleaner has the problem of inconvenient use because it is difficult to control the cleaner body that moves by following the above-mentioned operation of the dust suction nozzle through the rolling of the wheels on a surface to be cleaned.
As one means for solving this problem, an electric vacuum cleaner is proposed, which supports the cleaner body incorporating the intake fan in a floating manner on a surface to be cleaned, and moves and controls the cleaner body in a floating state by pushing and pulling a control handle attached to a part of the cleaner body (see, for example, Japanese Patent No. 3468401).
This electric vacuum cleaner has a dust suction port formed in the lower face of the cleaner body facing a surface to be cleaned and connected to the suction side of the intake fan, and an exhaust port connected to the outlet side of the intake fan. The electric vacuum cleaner sucks and collects dust from the dust suction port by negative pressure produced on the suction side when the intake fan is driven, while blows exhaust air of positive pressure produced on the outlet side onto the surface to be cleaned through the exhaust port, and supports the cleaner body in a floating manner on the surface to be cleaned by the function of the exhaust air.
With this structure, by applying slight force to the grip, it is possible to move the cleaner body supported in a floating manner on a surface to be cleaned in various directions without resistance over the surface to be cleaned, thereby facilitating handling of the electric vacuum cleaner and achieving more convenient use.
However, in the electric vacuum cleaner disclosed in Japanese Patent No. 3468401, since the dust suction port and the exhaust port are formed side by side in the lower face of the cleaner body, there is a possibility that the exhaust air blown from the exhaust port may interfere with the suction of dust into the dust suction port. Moreover, when the cleaner body floats from a surface to be cleaned due to the function of the exhaust air, the dust suction port also separates from the surface to be cleaned, and therefore there is a problem that the force of sucking dust into the dust suction port decreases and it is hard to achieve desired dust sucking efficiency.
In addition, when the intake fun is not driven, since there is no floating force caused by exhaust air, the whole cleaner body is in contact with a surface to be cleaned. In this state, it is difficult to move the electric vacuum cleaner, and forced movement and operation may damage the surface to be cleaned.
Further, since the dust collection chamber in a mid part of the intake channel is integrally formed together with the intake fan, intake channel and discharge channel inside the cleaner body, the cleaner body that is caused to float by the function of exhaust air becomes larger in size and may cause problems in the operation on a surface to be cleaned.